System for safe power loss for an electrodynamic burner

ABSTRACT

A system may be configured to modify one or more combustion parameters responsive to a loss of application of electrical energy to the combustion reaction.

The present application claims priority benefit from U.S. Provisional Patent Application No. 61/727,103, entitled “SYSTEM FOR SAFE POWER LOSS FOR AN ELECTRODYNAMIC BURNER”, filed Nov. 15, 2012; and U.S. Provisional Patent Application No. 61/725,095, entitled “FAIL-SAFE ELECTRODYNAMIC BURNER”, filed Nov. 12, 2012; and U.S. Provisional Patent Application No. 61/717,371, entitled “LIFTED FLAME FAIL-SAFE LOW NOx BURNER”, filed Oct. 23, 2012; and each of which, to the extent not inconsistent with the disclosure herein, is incorporated by reference.

SUMMARY

According to an embodiment, a system for applying electrical energy to a combustion reaction supported by a burner includes a voltage source configured to output a voltage and an electrodynamic system configured to receive the voltage from the voltage source and apply electrical energy to a combustion reaction. A power loss control circuit is configured to modify one or more combustion parameters of the combustion reaction responsive to a loss of the application of the electrical energy to the combustion reaction by the electrodynamic system.

According to an embodiment, a method for controlling a combustion reaction includes sensing a feedback parameter corresponding to the application of electrical energy to a combustion reaction, determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped, and causing a modification of one or more combustion parameters of the combustion reaction responsive to the stopping or probability of stopping the application of electrical energy to the combustion reaction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a burner including an electrodynamic system and a power loss control circuit, according to an embodiment.

FIG. 2 is a block diagram of a burner including an electrodynamic system and a power loss control circuit, according to another embodiment.

FIG. 3 is a block diagram of a burner including an electrodynamic system and a power loss control circuit, according to another embodiment.

FIG. 4A is a diagram of a burner including an electrodynamic system and a power loss control circuit, according to an embodiment.

FIG. 4B is a diagram of a burner including an electrodynamic system and a power loss control circuit of FIG. 4A in a configuration corresponding to a time after power loss, according to an embodiment.

FIG. 5 is a flowchart showing a method for operating a power loss control circuit for a burner including an electrodynamic system, according to an embodiment.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the disclosure.

FIG. 1 is a block diagram of a burner including an electrodynamic system 108 and a power loss control circuit 110, according to an embodiment. A system 100 for applying electrical energy to a combustion reaction 102 includes a burner 104, a voltage source 106, an electrodynamic system 108 and a power loss control circuit 110. The voltage source 106 is configured to output a voltage. The electrodynamic system 108 is configured to receive the voltage from the voltage source 106 and apply electrical energy to a combustion reaction 102. The power loss control circuit 110 is configured to modify one or more combustion parameters of the combustion reaction 102 responsive to a loss of the application of the electrical energy to the combustion reaction 102 by the electrodynamic system 108.

Various embodiments are contemplated for the voltage source 106. The voltage source can, for example, include a linear power supply, a switching power supply, and/or a voltage multiplier. In an embodiment, the voltage source includes linear and/or switched mode power supply sections that output a chopped signal to a voltage multiplier. For example, the power supply sections can output a chopped DC waveform at 0 to +12 volts. The voltage source 106 can also include an 11-stage positive polarity voltage multiplier that receives the chopped DC waveform and multiplies it to about 24,000 volts for output to the charging mechanism 104. The voltage source 106 can also include one or more power supply sections that output a second chopped DC waveform at 0 to −12 volts. The voltage source 106 can include a second voltage multiplier, for example a 10 stage negative polarity voltage multiplier that receives the second chopped DC waveform and multiplies it to about −12,000 volts for output to the flame support electrode 122.

The system 100 may include a subsystem configured to receive heat from the combustion reaction 102.

The electrical energy applied by the electrodynamic system 108 can include electric charge, electric voltage, and/or an electric field. The electrodynamic system 108 can be configured to cause the combustion reaction to operate according to an electrically-supported combustion regime that would be unstable or unsustainable without the application of the electrical energy. For example, the electrically-supported combustion regime can include combustion at high fuel dilution. Additionally or alternatively, the electrically-supported combustion regime can include combustion with low oxides of nitrogen (NOx) output. Additionally or alternatively, the electrically-supported combustion regime can include combustion of at least one fuel with limited flammability. The instability or unsustainability can include an increased probability of flame blow-out.

The power loss control circuit 110 can include one or more actuators 112 configured to control the one or more combustion parameters and control circuitry 114 configured to control the one or more actuators 112. An actuator drive circuit 116 can be operatively coupled to the one or more actuators 112. A controller circuit 118 can be operatively coupled to the actuator drive circuit 116, the controller circuit being configured to drive the actuator drive circuit 116 responsive to the loss of the application of electrical energy to the combustion reaction.

The controller circuit 118 can be operatively coupled to an electrical energy source 120 configured to provide electrical energy to the voltage source 106. The controller circuit 118 can be configured to drive the actuator drive circuit 116 responsive to a loss of electrical energy at the electrical energy source 120. Additionally or alternatively, the controller circuit 118 can be operatively coupled to the voltage source 106 and be configured to drive the actuator drive circuit 116 responsive to a loss of electrical energy from the voltage source 106.

FIG. 2 is a block diagram of a burner 200 including an electrodynamic system 108 and a power loss control circuit 110, according to another embodiment. The controller circuit 118 can be operatively coupled to an output 202 from the voltage source to the electrodynamic system 106, 108 or can be operatively coupled to the electrodynamic system 108. The controller circuit 118 can be configured to drive the actuator drive circuit 116 responsive to a loss of electrical energy from the voltage source 106 or from the electrodynamic system 108.

FIG. 3 is a block diagram of a burner 300 including an electrodynamic system 108 and a power loss control circuit 110, according to another embodiment. One or more sensors 302 can be configured to sense one or more combustion parameters. The controller circuit 118 can be operatively coupled to the one or more sensors 302. The controller circuit 118 can be configured to drive the actuator drive circuit 116 responsive to a sensed combustion parameter corresponding to the loss of application of electrical energy to the combustion reaction. For example, the sensor(s) can include a voltage sensor. In another example, the sensor(s) can include a pyrometer, an infrared sensor, an image sensor, or another sensor configured to sense a parameter correlated to flame 102 stability.

Referring to FIGS. 1-3, the power loss control circuit 110 can include an uninterruptable power source 124 operatively coupled to the control circuitry 114 and configured to provide power to the control circuitry 114 to operate the one or more actuators 112. The uninterruptable power source 124 can include an energy storage circuit, such as one or more batteries.

Various actuator 112 arrangements are contemplated. For example, the actuator(s) 112 can include a fuel valve 126 or fuel delivery mechanism. The control circuitry 114 can be configured to cause the fuel valve 126 or fuel delivery mechanism to reduce a rate of fuel delivery or stop fuel delivery to the combustion reaction 102 responsive to a loss of the application of the electrical energy to the combustion reaction by the electrodynamic system 108. The actuator(s) 112 can additionally or alternatively include an air or flue gas damper 128 or oxidizer delivery mechanism. The control circuitry 114 can be configured to cause the air or flue gas damper 128 or oxidizer delivery mechanism to reduce a rate of oxidizer delivery or stop oxidizer delivery to the combustion reaction 102 or to reduce an amount of dilution of a fuel prior to combustion responsive to the loss of the application of the electrical energy to the combustion reaction 102 by the electrodynamic system 108. The actuator(s) 112 can additionally or alternatively include an aerodynamic flame holder actuator 130. The control circuitry 114 can be configured to cause the aerodynamic flame holder actuator 130 to hold the combustion reaction at a high stability location responsive to the loss of the application of the electrical energy to the combustion reaction 102 by the electrodynamic system 108. The actuator(s) can additionally or alternatively include an igniter 132. The control circuitry 114 can be configured to cause the igniter 132 to ignite the combustion reaction 102 at a high stability location responsive to the loss of the application of the electrical energy to the combustion reaction 102 by the electrodynamic system 108.

FIG. 4A is a diagram of a burner 400 including an electrodynamic system and a power loss control circuit, according to an embodiment. FIG. 4B is a diagram of a burner including an electrodynamic system and a power loss control circuit of FIG. 4A in a configuration 401 corresponding to a time after power loss, according to an embodiment. A fuel nozzle 422 can be configured to deliver a fuel stream 404 to support a combustion reaction 102. The fuel stream 404 can include a diverging fuel stream 404 that becomes successively more dilute with distance from the fuel nozzle 422. The divergence of the stream can typically correspond to entrainment of air or flue gas adjacent to the fuel stream 404. Accordingly, the term “fuel stream” can refer to substantially pure fuel or diluted fuel.

Referring to FIGS. 4A and 4B, the electrodynamic system 108 can include a charging mechanism 402 operatively coupled to the voltage source 106. The charging mechanism 402 can be configured to apply a first charge or voltage to the combustion reaction 102 or a fuel stream 404 supporting the combustion reaction. One or more field electrodes 406 can be operatively coupled to the voltage source 106 and disposed to apply an electric field or second charges to the combustion reaction 102. The electric field or second charges can be selected to enhance combustion. A first flame support surface 408 can be disposed adjacent to the fuel stream 404 and be configured to support the flame 102 when the charge or voltage is applied to the flame 102 or the fuel stream 404.

An aerodynamic flame holder 410 can be disposed adjacent to or away from the fuel stream 404. The aerodynamic flame holder 410 can be configured, when engaged, to hold the combustion reaction 102 at a more stable location than the location at which the combustion reaction is held by the first flame support surface 408. A flame position actuator can be configured to selectively engage the aerodynamic flame holder 410 with the fuel stream 404 to cause the aerodynamic flame holder 410 to support the combustion reaction 102 when the charge or voltage is not applied to the combustion reaction 102 or fuel stream 404. A power loss control circuit 110 can be configured to drive the flame position actuator to cause the combustion reaction to be supported by the aerodynamic flame holder when the charge or voltage is not applied to the combustion reaction or fuel stream.

The power loss control circuit 110 can include an uninterruptable power source 124 and control circuitry 118 operatively coupled to the uninterruptable power source 124. An actuator drive 116 can be operatively coupled to the control circuitry 118. The actuator drive 116 can include an igniter controller. An actuator 112 including an igniter 132 can be operatively coupled to the igniter controller 116. The control circuitry 118 can be configured to sense the loss of application of electrical energy to the combustion reaction 102 or to a fuel stream 404 supporting the combustion reaction 102, and responsively cause the igniter controller 116 to drive the igniter 132 to ignite the fuel stream 404 adjacent to the aerodynamic flame holder 410. Ignition of the fuel stream 404 adjacent to the aerodynamic flame holder 410 can be selected to cause the combustion reaction 102 to be held in a high stability location by the aerodynamic flame holder 410 (see FIG. 4B).

The control circuitry 118 can include a sensor 412 configured to sense a voltage proportional to a voltage output by the voltage source 106 and a normally open switch 414 configured to maintain an open circuit between the uninterruptable power source 124 and the actuator drive 116 when a non-zero voltage proportional to the voltage output by the voltage source 106 is sensed. The sensor 412 can include a node of a voltage divider including at least two resistors 416, 418 forming a path to ground 420 for an output 202 from the voltage source 106. The normally open switch can include a field effect transistor (FET) or an insulated gate bipolar transistor (IGBT), for example.

The power loss control circuit 110 can additionally or alternatively include a microcontroller configured to execute computer executable instructions. Additionally or alternatively, the power loss control circuit 110 can include a microprocessor (not shown); and a computer memory (not shown) operatively coupled to the microprocessor. The computer memory can include a non-transitory computer-readable medium carrying computer executable instructions. The microprocessor can be configured to execute the computer executable instructions to cause the to cause the modification of the one or more combustion parameters of the combustion reaction responsive to the loss of the application of the electrical energy to the combustion reaction 102 by the electrodynamic system 108.

FIG. 5 is a flowchart showing a method 500 for operating a power loss control circuit for a burner including an electrodynamic system, according to an embodiment. Heat energy can be transferred from the combustion reaction to one or more of a chemical process, furnace, boiler, propulsion system, and/or electrical power generation system, for example.

A combustion reaction is supported in step 502. Supporting the combustion reaction may include providing one or more of a gas, liquid, and/or solid fuel.

In step 504, electrical energy is applied to the combustion reaction. Application of electrical energy to the combustion reaction can include operating an electrodynamic system. Additionally or alternatively, applying electrical energy to the combustion reaction can include applying an electrical field to the combustion reaction, applying a voltage to the combustion reaction, and/or applying electrical charges to the combustion reaction. The application of the electrical energy to the combustion reaction can include causing enhanced mixing of an oxidizer and fuel and/or can include causing an enhanced rate of reaction.

In step 504, according to an embodiment, application of electrical energy to the combustion reaction can cause the combustion reaction to produce reduced oxides of nitrogen (NOx). Additionally or alternatively, the application of electrical energy to the combustion reaction can cause an increase in thermal radiation. Additionally or alternatively, the application of electrical energy to the combustion reaction can cause flattening the combustion reaction with an electric field. Additionally or alternatively, the application of electrical energy to the combustion reaction can cause the combustion reaction to occur at a location where the combustion reaction would not occur without the application of the electrical energy. Additionally or alternatively, the application of electrical energy to the combustion reaction can cause the combustion reaction to be stable under a condition that would cause the combustion reaction to be unstable without the application of the electrical energy.

Proceeding to step 506, a feedback parameter corresponding to the application of electrical energy to a combustion reaction is sensed. Sensing the feedback parameter can include sensing a feed forward parameter. Step 506 can include sensing a voltage proportional to a voltage output by a voltage source to an electrodynamic system, sensing a voltage proportional to a voltage provided to a voltage source configured to power an electrodynamic system, or sensing a voltage proportional to a voltage, electric charge, and/or electric field applied to the combustion reaction. Sensing the feedback parameter can include operating a sensor. The sensor can be configured to sense the feedback parameter proximate to the combustion reaction.

In step 508 it is determined when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped. Step 508 can include closing a normally-open switch responsive to a loss of voltage on a sense node.

Step 508 can include operating passive electrical circuitry, or can include operating a microcontroller and/or microprocessor to monitor the feedback parameter. Determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped can, in some embodiments, consist essentially of determining when a voltage drops below a threshold.

The method 500 can include step 510, back-up electrical power is received. Step 510 can include powering a power loss control circuit with back-up electrical power.

Proceeding to step 512, a modification of one or more combustion parameters of the combustion reaction is caused responsive to the stopping or probability of stopping the application of electrical energy to the combustion reaction. Modification of the one or more combustion parameters can include stopping the combustion reaction and/or can include reducing a heat output of the combustion reaction. Step 512 can include causing the combustion reaction to continue without the application of the electrical energy. Step 512 can include causing the combustion reaction to occur in a location different from a location where the combustion reaction occurred while receiving the electrical energy.

Step 512 can include operating an actuator to change the one or more combustion parameters. Operating an actuator to change the one or more combustion parameters can include operating a fuel valve and/or fuel delivery mechanism 126 to change a delivery rate of fuel to the combustion reaction. Additionally or alternatively, operating an actuator to change the one or more combustion parameters can include operating an air or flue gas damper to reduce an amount of fuel dilution and/or can include operating an oxidizer delivery mechanism to change the amount of oxidizer delivery. Additionally or alternatively, operating an actuator to change the one or more combustion parameters can include operating a flame position actuator to change the location of the combustion reaction. For example, an aerodynamic flame holder actuator and/or a fuel nozzle actuator can be operated to bring a fuel stream 404 into close proximity with or contacting an aerodynamic flame holder 410. Additionally or alternatively, operating an actuator to change the one or more combustion parameters can include operating an igniter 132 to ignite a fuel stream. For example, the fuel stream can be ignited in a location that is more stable than a location used during operation of the electrodynamic system.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims. 

1. A system for applying electrical energy to a combustion reaction supported by a burner, comprising: a voltage source configured to output a voltage; an electrodynamic system configured to receive the voltage from the voltage source and apply electrical energy to a combustion reaction; and a power loss control circuit configured to modify one or more combustion parameters of the combustion reaction responsive to a loss of the application of the electrical energy to the combustion reaction by the electrodynamic system.
 2. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, further comprising the burner.
 3. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, further comprising a subsystem configured to receive heat from the combustion reaction.
 4. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the electrical energy includes one or more of electric charge, electric voltage, or an electric field
 5. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the electrodynamic system is configured to cause the combustion reaction to operate according to an electrically-supported combustion regime that would be unstable or unsustainable without the application of the electrical energy.
 6. The system for applying electrical energy to a combustion reaction supported by a burner of claim 5, wherein the electrically-supported combustion regime includes combustion at high fuel dilution.
 7. The system for applying electrical energy to a combustion reaction supported by a burner of claim 5, wherein the electrically-supported combustion regime includes combustion with low oxides of nitrogen (NOx) output.
 8. The system for applying electrical energy to a combustion reaction supported by a burner of claim 5, wherein the electrically-supported combustion regime includes combustion of at least one fuel with limited flammability.
 9. The system for applying electrical energy to a combustion reaction supported by a burner of claim 5, wherein the instability or unsustainability includes an increased probability of flame blow-out.
 10. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the power loss control circuit further comprises: one or more actuators configured to control the one or more combustion parameters; and control circuitry configured to control the one or more actuators.
 11. The system for applying electrical energy to a combustion reaction supported by a burner of claim 10, wherein the control circuitry further comprises: an actuator drive circuit operatively coupled to the one or more actuators; and a controller circuit operatively coupled to the actuator drive circuit, the controller circuit being configured to drive the actuator drive circuit responsive to the loss of the application of electrical energy to the combustion reaction. 12-14. (canceled)
 15. The system for applying electrical energy to a combustion reaction supported by a burner of claim 11, further comprising: one or more sensors configured to sense one or more combustion parameters; wherein the controller circuit is operatively coupled to the one or more sensors; and wherein the controller circuit is configured to drive the actuator drive circuit responsive to a sensed combustion parameter corresponding to the loss of application of electrical energy to the combustion reaction.
 16. The system for applying electrical energy to a combustion reaction supported by a burner of claim 10, wherein the power loss control circuit further comprises an uninterruptable power source operatively coupled to the control circuitry and configured to provide power to the control circuitry to operate the one or more actuators. 17-18. (canceled)
 19. The system for applying electrical energy to a combustion reaction supported by a burner of claim 10, wherein the one or more actuators comprises a fuel valve or fuel delivery mechanism.
 20. (canceled)
 21. The system for applying electrical energy to a combustion reaction supported by a burner of claim 10, wherein the one or more actuators comprises an air or flue gas damper or oxidizer delivery mechanism.
 22. (canceled)
 23. The system for applying electrical energy to a combustion reaction supported by a burner of claim 10, wherein the one or more actuators comprises an aerodynamic flame holder actuator.
 24. (canceled)
 25. The system for applying electrical energy to a combustion reaction supported by a burner of claim 10, wherein the one or more actuators comprises an igniter.
 26. (canceled)
 27. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the electrodynamic system further comprises: a charging mechanism operatively coupled to the voltage source and configured to apply a first charge or voltage to the combustion reaction or a fuel stream supporting the flame; one or more field electrodes operatively coupled to the voltage source and disposed to apply an electric field or second charges to the combustion reaction, the electric field or second charges being selected to enhance combustion; and a first flame support surface disposed adjacent to the fuel stream configured to support the flame when the charge or voltage is applied to the flame or the fuel stream.
 28. The system for applying electrical energy to a combustion reaction supported by a burner of claim 27, further comprising: an aerodynamic flame holder disposed adjacent to or away from the fuel stream, the aerodynamic flame holder being configured, when engaged, to hold the combustion reaction at a more stable location than the location at which the combustion reaction is held by the first flame support surface.
 29. (canceled)
 30. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the power loss control circuit further comprises: an uninterruptable power source; a controller circuit operatively coupled to the uninterruptable power source; an actuator drive operatively coupled to the controller circuit, the actuator drive including an igniter controller; and an actuator including an igniter operatively coupled to the igniter controller; wherein the controller circuit is configured to sense the loss of application of electrical energy to the combustion reaction or to a fuel stream supporting the combustion reaction, and responsively cause the igniter controller to drive the igniter to ignite the fuel stream adjacent to the aerodynamic flame holder.
 31. The system for applying electrical energy to a combustion reaction supported by a burner of claim 30, wherein the ignition of the fuel stream adjacent to the aerodynamic flame holder is selected to cause the combustion reaction to be held in a high stability location by the aerodynamic flame holder.
 32. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the power loss control circuit further comprises: an uninterruptable power source; a controller circuit operatively coupled to the uninterruptable power source; an actuator drive operatively coupled to the controller circuit; and an actuator operatively coupled to the igniter controller; wherein the controller circuit is configured to sense the loss of application of electrical energy to the combustion reaction or to a fuel stream supporting the combustion reaction, and responsively cause the actuator drive to drive the actuator to control a combustion parameter to increase combustion reaction stability.
 33. The system for applying electrical energy to a combustion reaction supported by a burner of claim 32, wherein the controller circuit includes a sensor configured to sense a voltage proportional to a voltage output by the voltage source; and a normally open switch configured to maintain an open circuit between the uninterruptable power source and the actuator drive when a non-zero voltage proportional to the voltage output by the voltage source is sensed. 34-35. (canceled)
 36. The system for applying electrical energy to a combustion reaction supported by a burner of claim 33, wherein the normally open switch includes an insulated gate bipolar transistor (IGBT).
 37. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, further comprising a fuel nozzle configured to deliver the fuel stream.
 38. The system for applying electrical energy to a combustion reaction supported by a burner of claim 1, wherein the power loss control circuit includes a microcontroller configured to execute computer executable instructions.
 39. (canceled)
 40. A method for controlling a combustion reaction, comprising: sensing a feedback parameter corresponding to the application of electrical energy to a combustion reaction; determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped; and causing a modification of one or more combustion parameters of the combustion reaction responsive to the stopping or probability of stopping the application of electrical energy to the combustion reaction.
 41. The method for controlling the combustion reaction of claim 40, further comprising: transferring heat energy from the combustion reaction to one or more of a chemical process, furnace, boiler, propulsion system, or electrical power generation system.
 42. The method for controlling the combustion reaction of claim 40, further comprising: receiving back-up electrical power.
 43. The method for controlling the combustion reaction of claim 42, further comprising: powering a power loss control circuit with the back-up electrical power.
 44. The method for controlling the combustion reaction of claim 40, further comprising: supporting the combustion reaction.
 45. The method for controlling the combustion reaction of claim 44, wherein supporting the combustion reaction includes providing one or more of a gas, liquid, or solid fuel.
 46. The method for controlling the combustion reaction of claim 40, further comprising: applying the electrical energy to the combustion reaction. 47-57. (canceled)
 58. The method for controlling the combustion reaction of claim 40, wherein sensing the feedback parameter includes sensing a feed forward parameter.
 59. The method for controlling the combustion reaction of claim 40, wherein sensing the feedback parameter includes sensing a voltage proportional to a voltage output by a voltage source to an electrodynamic system, sensing a voltage proportional to a voltage provided to a voltage source configured to power an electrodynamic system, or sensing a voltage proportional to a voltage, electric charge, or electric field applied to the combustion reaction.
 60. The method for controlling the combustion reaction of claim 40, wherein sensing the feedback parameter includes operating a sensor configured to sense the feedback parameter proximate to the combustion reaction.
 61. The method for controlling the combustion reaction of claim 40, wherein determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped includes closing a normally-open switch responsive to a loss of voltage on a sense node.
 62. The method for controlling the combustion reaction of claim 40, wherein determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped includes operating passive electrical circuitry.
 63. The method for controlling the combustion reaction of claim 40, wherein determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped includes operating a microcontroller or microprocessor to monitor the feedback parameter.
 64. The method for controlling the combustion reaction of claim 40, wherein determining when the application of electrical energy to the combustion reaction is stopped or has a probability of being stopped consists essentially of determining when a voltage drops below a threshold.
 65. The method for controlling the combustion reaction of claim 40, wherein causing the modification of the one or more combustion parameters includes stopping the combustion reaction.
 66. The method for controlling the combustion reaction of claim 40, wherein causing the modification of the one or more combustion parameters includes reducing a heat output of the combustion reaction.
 67. The method for controlling the combustion reaction of claim 40, wherein causing the modification of the one or more combustion parameters includes causing the combustion reaction to continue without the application of the electrical energy.
 68. The method for controlling the combustion reaction of claim 40, wherein causing the modification of the one or more combustion parameters includes causing the combustion reaction to occur in a location different from a location where the combustion reaction occurred while receiving the electrical energy.
 69. The method for controlling the combustion reaction of claim 40, wherein causing the modification of one or more combustion parameters includes operating an actuator to change the one or more combustion parameters.
 70. (canceled)
 71. The method for controlling the combustion reaction of claim 69, wherein operating an actuator to change the one or more combustion parameters includes operating an air or flue gas damper to reduce an amount of fuel dilution.
 72. The method for controlling the combustion reaction of claim 69, wherein operating an actuator to change the one or more combustion parameters includes operating an oxidizer delivery mechanism to change the amount of oxidizer delivery.
 73. The method for controlling the combustion reaction of claim 69, wherein operating an actuator to change the one or more combustion parameters includes operating a flame position actuator to change the location of the combustion reaction. 74-75. (canceled) 